Of Turtles and Spartans
by Koriat Cyredanthem
Summary: What if the Slipspace rupture that tore the Forward Unto Dawn in half bent time and space? When they meet the turtles, John starts to realize just what he missed in life, growing up as a child soldier and being a warrior all his life. Is it ironic that it takes the friendship of a different species to make the Spartan feel human? [Please review!]
1. Chapter 1

_Well… I don't know what to say about this except… Enjoy? I'm in quite a bit of pain daily and taking narcotics to battle it, so maybe that's where this one came from… Anyway. Crossover fic. Written for pure enjoyment. I don't even know who the bad guy is yet. I might continue, or this might just be a one-shot._

_Disclaimer: Neither sets are mine. I may introduce OC, in which case, those _are_ mine. _

**Chapter 1: Wormholes, They Suck**

Cortana flowed freely, sampling data as the _Dawn_'s low-power systems continually sent out the mayday signal and retrieved information as the hulk of the ship floated through space. She didn't know where they were – Nav was still down – but she was getting closer to fixing it, if she could just…

_They lied to you!_

Cortana flinched. The scream echoed throughout her main code. She chased down the shadow copy of herself, erased it form her own code, and returned to examining the reports from the ship's single functional long-range camera.

There. Cortana focused her attention on a small anomaly. It was probably nothing – a glitch, or another far-off radio-emitting star fooling the instruments.

But, no. This was different. Intrigued now, Cortana boosted the camera just _slightly_ and clarified the data. It wasn't a Slipspace hole, at least not that she recognized, but there were elements to the readings…

_What in the universe?_ she asked herself, moving the ship towards the far-off anomaly. As they approached – slowly; she couldn't waste fuel to do so quickly, much as her curiosity burned – the anomaly fluctuated and then…

"Shit!" In her alarm, Cortana appeared on the holodeck in the cryo bay as though there were humans around to whom to communicate the change in the anomaly. However, the only other creature on the ship was her friend and protector, John-117, and he was frozen solid. Besides, even if someone _had_ been there, being in space without internal atmosphere meant the sound waves would never have carried anyway.

The anomaly seemed to flex and reach out towards the ship; Cortana dumped more power into the reverse engines, but they sputtered slightly and only managed to decrease the ship's forward movement by 10% before the anomaly had them.

"No, no, no," Cortana muttered. Another shadow clone screeched through her code, but Cortana had more important things to concentrate on at the moment than rampant figments of her code.

The anomaly had them. They were accelerating. The ship groaned and then began to shatter catastrophically. The outside hull began sheering off and would have made horrible noises if they hadn't been in the vacuum of space. Cortana estimated that she had all of ten minutes before John's cryo tube was disconnected from the main power supply, leaving him with several days of back-up power before the tube would serve as a tomb.

Cortana could only watch as she transferred herself into the _tiny_ data chip stored in the cryo tube's main computer. She had to compress a lot of data to do it – and still felt pressed. All she could do now was access the cryo tube's emergency beacon, which she turned on, and count the seconds. They went by agonizingly slow.

Then she counted the 548th second and the cryo tube's computer suddenly scrambled power sources. The main supply was off-line; she and the computer programs were all crammed into the tube's tiny processor. The automatic programming raced around, setting up the back-up power and switching on the emergency locator – redundant, since she'd already done it manually, but the computer did what it was programmed to do.

Cortana remotely accessed what was left of the _Dawn's_ systems. They were through the anomaly. The ship's badly-abused systems were reading… Normal. Normal space, normal time, no dilation…

Cortana activated the long-range camera and pointed it out the back of the ship. It was stuck, however, the gears broken by one of those shuddering convulsions of a torn ship, and she could only "see" a handful of black space around the torn piece of shielding that had been ripped up.

However, that handful of space provided at least some answers. There were some stars. She zoomed in and recognized the Eagle Nebula. Blinking, Cortana eagerly compared the handful of sky to her star charts, and nearly woke John then and there. Instead, containing her excitement, Cortana jumped back to the main ship's systems and began unpacking.

It was another 40,382.847 seconds – or 673 minutes, or 112 hours, or 0.47 Earth days – before Cortana managed to decompress all of the data in her system and check it over for errors and mistakes.

Cortana ran many checks on her conclusion. She allowed for a small margin of error due to the camera's abuse, but there was a 99.5% chance she was correct.

Before waking John, however, Cortana would attempt to establish communication.

"_Dawn_ to UNSC Earth command, do you read?"

There was silence on the other end of the radio. _Perhaps we can't boost a signal that far,_ Cortana said to herself, more as a consolation than truth. She tried hailing the outposts closer by – on Mars, first, then on Io and even the station orbiting Neptune. Nothing replied.

Cortana opened all frequencies and made a wide-range broadcast.

"This is Cortana of the _UNSC Forward Unto Dawn,_ does anyone copy? I repeat, this is Artificial Intelligence Cortana, serial number CTN 0452-9, looking for any UNSC personnel to reply on any frequency."

_Please tell me we're not too late. _They had spent three years in space so far… Maybe the war had ended with humanity's destruction.

However, joy made her avatar turn a decidedly pinkish hue as the radio crackled back to life on a frequency only used by short-range in-system communique.

"This is General Jenkins. Who is this and why are you broadcasting on a secure military channel?"

Cortana didn't have a General Jenkins in her UNSC files, but it was possible the UNSC had shuffled new people into the brass within the last three years.

"This is AI 0452-9, Cortana. I have Spartan Sierra-117 on board and request immediate evac at my location. Power systems are failing and the ship is falling apart. We have been through-"

"Alright, what kind of sick joke is this?" General Jenkins demanded. He sounded angry.

"General, this is no joke. We've been missing for three years, I know, but as I was saying, we have come through a space anomaly – I will transmit all relevant information as soon as-"

"What's your authorization code to use this channel? I'll have your stripes for this!"

"Sir, I am broadcasting on all frequencies as no one replied to the standard mayday channel. I have no stripes – I'm an AI." General Jenkins must _really_ be new.

"Yeah, yeah, and I'm the queen of Australia."

Now _that _triggered curiosity in Cortana. "Australia doesn't have a queen, sir…"

"Don't get snippy with me. Your name and rank, soldier. I'll have you discharged from the corp for this!"

Rather than talk to the lunatic general, Cortana tried another approach. The Dawn's engines were functioning, barely, and Cortana plotted a course in-system.

"We are approaching on the following vector," she told the General. "As I said, I have Sierra-117 on board and will require a cryoteam to revive him. We should pass Mars in eight hours and be within reach of an orbital maintenance platform within ten hours."

"Mars? What kind of drugs are you on, you idiot?"

Cortana just shook her head. "Sir, per UNSC protocol, I am requesting a transfer of radio communication to your supervisor, or, failing that, could I _please_ talk to Admiral Hood?"

"There is no Admiral Hood here."

Cortana processed a feeling of sadness. Lord Hood had been a good man, capable Admiral, and loyal soldier. "He has been KIA, then?" she asked.

"Listen, lady, there's no Admiral Hood on any of our rolls, so I don't know what the hell kind of mushrooms you're on, but I'm just getting the trace on your radio and… Wait, is this right?" General Jenkins was talking to someone else, apparently.

"We are just outside of Jupiter's orbit and about to pass through the asteroid field," Cortana said smoothly. "You should see us on the long-range cameras. I have no visual of you yet."

"That's fucking impossible."

Cortana didn't know what to say to that.

"The United States Marines do not recognize you or your ship, alien, so you'd best be turning around and getting the hell out of our airspace before we launch nuclear weapons." This was a new voice, again male.

Cortana processed the threat. Nukes would damage the _Dawn_ further, but why was Earth threatening to shoot down a ship containing a Spartan on it?

"Did you hear me correctly, sir?" she asked. "I have Sierra-117 on board-"

"And whatever the hell it is, we don't want it! Earth is a no-alien zone."

"_He_ needs medical attention immediately," Cortana snarled. "And _he_ saved your asses from Truth and his fleet, not to mention all the other Covenant bastards we've dealt with for you. You could show some respect, you ignorant idiot. Haven't you ever heard of the Spartans before?"

A rampant copy screamed obscenities into the radio for a moment and Cortana hesitated long enough to let it thoroughly cuss-out the men on the other end of the radio – she couldn't, after all – before destroying it.

"Look, I don't know who you think you are – or where you think you are, for that matter – but if you approach Earth's atmosphere, we will fire upon you."

The radio clicked off with a finality Cortana didn't need an "over" for. She sighed and activated her avatar on the holodeck in the cryo bay. "Well, John, I guess we're lost… Again."

She sighed and went back to examining the handful of space her long-range camera had shown her. With a frown on her avatar, Cortana compared it to known star charts of the region around Earth.

What she found made her both ecstatic and deeply troubled. The anomaly had bent space _and_ time. They were in the Sol system, alright, but it was currently sometime in the early 21st century, if she compensated for stellar drift and progression.

Dredging up her history books, Cortana quickly read everything they knew about the Earth of 2000-2100.

"Well, butter my biscuit, but we could very well be screwed," Cortana muttered to herself, using a popular turn of phrase from the period. She kept the ship on course for Earth – John needed medical attention whether she liked it or not, and his cryotube would run out of power fairly soon. Cortana settled in to wait as the ship approached Earth.

"Warning: Incoming vehicle."

One of the only functioning sensors on the ship blared a close-proximity warning just as Cortana "parked" the _Dawn_ in a geosynchronous orbit over Mars to hide it from direct view of Earth, just in case those lunatics on the radio decided to fire nukes at her.

The trajectory of the ship was decidedly non-hostile. Cortana couldn't "see" it, but the thing's heat signature was clear; it was propelled by ancient fuel technology.

The AI could do nothing, though, with the ship's barely-holding frame. The stress of holding even this position would eventually tear the ship apart, if they didn't run out of power first.

The approaching ship came right into the docking bay, according to the onboard internal cameras. Cortana watched avidly as four shorter humans exited the craft and made their way into the ship. There was no audio, but by their movements, they were clearly speaking to each other.

All four were shorter than the average human, especially since the space suits added a couple extra inches. They were bulky suits, definitely fitting the early 21st century theory. Each human had something wide and oval-shaped across their back, and their gloves were split to group the index and middle fingers in one pocket with the pink and ring fingers in another, the thumb occupying its normal position. None of them wore any sort of identifying patch or rank.

The faceplates were heavily polarized so Cortana couldn't see their faces to read their lips and figure out what they were saying. It would be nice to know if she was encountering hostiles or friendlies. Judging by the military's response at first, however, and considering that history showed _no_ aliens approaching Earth before the Covenant attacked the outer colonies, she doubted they were here to help.

Something suddenly invaded the ship's systems. Degraded as they were, the dumb AI program managed to find the control for the ship's interior lights and turned them on. Cortana allowed the program free run of the system, except her own data stored behind several blockades, and studied it.

It seemed to be directly controlled by one of the four humans; he – or she – had plugged into one of the universal ports within the hallways and was typing rapidly away on a device that folded like a book on its side. It was a laptop, Cortana's files said, much like the individual holoscreens everyone carried around nowadays except much lower tech.

The lights came on and the program even managed to activate the spinning gravity generator in the ship's midsection. Cortana hadn't bothered – John couldn't tell the difference in cryo, after all – but the four humans were clearly glad to be able to move in the standard gee environment.

Cortana left tracers and led the dumb program to "find" the main control room – the cryo bay, in reality, but it couldn't tell the difference – and direct the four humans to it. Then she turned to waking John. He would want to be conscious for this.

The cryo tube had iced over slightly in the darkness and vacuum of space, and Cortana couldn't touch the manual release on this side, so she waited for John's brain to fully wake and then called softly through the tube's internal speakers, "John, can you hear me?"

John stirred slightly, his armor probably making several clunking noises inside the tube, and then his brain waves spiked and he woke fully. His first action – as any disoriented soldier would do, finding themselves trapped – was to pound his fists against the glass case holding him.

"John, calm down," Cortana ordered soothingly. John hadn't broken the seal, thankfully. He took a deep breath, swallowed several times – the nutrient mix fed into his environment by the tube was disgusting, Cortana had heard many soldiers complain, but the Spartan didn't seem to mind – and then coughed a few times to clear his throat.

"Where are we?" John asked.

"Sol system. We've got a lot to catch up on. It's been three years, John." John simply grunted quietly. "There are four people coming for you – they should be here momentarily. I woke you a little early because I don't think they could carry you and the tube back."

"Thanks," John said. "Open the tube."

"You'll have to pull the manual release lever above your head," Cortana replied.

John reached up; Cortana watched through her holographic avatar's eyes as he levered himself out of the tube and into the vacuum, his boots thudding onto the deck. "There's gravity," he murmured, almost to himself, but Cortana chose to answer as though he was addressing her.

"Yes, they turned that – and the lights – on. We don't have much power remaining. The ship was heavily damaged by the anomaly that brought us here. John, we're… Well, we traveled through time, I think. We're in an alternate dimension, or in our historical timeline… I can't really say for sure."

John unlatched his rifle – mostly empty, but it was a comfort gesture – from the side of the cryotube where he'd stored it before being frozen and processed that information. "Then where – and when – are we?"

"We're hovering over Mars at the moment," Cortana answered. "It's sometime in the early 21st century, I believe. Probably closer to 2000 than 2100, judging by what I could see from the long-range cameras."

"How do we get home?"

"That's a really good question," Cortana muttered. John seemed to notice the worry in her voice and put a hand on the holodeck in a silent "it's okay" gesture. "Well, let's see what our new friends have to say about a seven-foot-tall green robot. They're just about to round the corner."

It clearly took some serious self-control for John to hold the rifle at parade-rest across his chest and stand unprotected in the middle of the room, warned ahead of time by the approach of possible hostiles. The door slid open.

_~~CROSSOVER~~_

Leo shifted slightly from foot to foot, staring at the grey steel around them. "It's not Utrom," Donnie had said, captain of the obvious as always, as soon as they gotten onboard. But if it wasn't Utrom, what else had the capability of space flight and would be hiding in Mar's shadow?

"The control center is this way," Don said after a moment, holding up his laptop. A route was outlined in red. Most of the ship was clearly missing – the schematic was huge, Leo could tell that much. But the piece they had found was outlined in green on the blueprints, making up a little less than half of the actual ship.

"Let's go," Raph grunted. He hated space walks. At least they had gravity back.

The walk was quiet, though Don was admiring the grey steel, poking his nose into corridors, and generally being awe-struck. Mikey was pouting over the addition of gravity – he had enjoyed bouncing and gliding around the corridors.

"Just ahead," Don said into the radio. Leo let the braniac lead the way into what looked, at first, like a sealed door but opened when his brother approached.

Inside, Leo's first impression was of more grey steel, but this time, something large and green was clearly the centerpiece of the room. It was frozen for the first second while Leo examined it – it seemed to be a humanoid robot, probably around seven feet tall. There were many scratches and dents in its armor, and a "117" was printed on its left chest plate. Its arms were holding a gun or something like it.

That robot caught Raph's attention, too, but Don and Mikey were clearly more interested in the blue-purple glow at the robot's elbow. Leo looked at it, too, and frowned. The glow _looked_ like a tiny woman, with darker purple lines on her skin, but Leo could clearly see the back of the room through her as well.

Suddenly, the robot shifted slightly, raising the gun slightly, and Leo crouched defensively. His brothers did the same.

"We're not going to hurt you."

The voice was feminine, gentle, and coming through Leo's earpiece. Don gasped quietly and then asked before Leo could interrupt, "Are you in my radio?"

There was a soft chuckle and the robot settled into what Leo recognized as watchful stillness, but the blue-purple woman on the pedestal waved her hand. "Over here," she said over the radio. "I am Cortana, an artificial intelligence."

"An AI?" Don sounded like Christmas had come early. Leo sighed quietly to himself; they needed answers _before_ the genius launched into a lecture or, God forbid, a series of questions that could numb your ears.

"What are you and what are you doing here?" Leo asked, moving forward to identify himself as the one speaking and motioning for Don to hold his questions for the moment.

"I'm an AI, like I said." The avatar's lips were moving, but Don had explained that sound didn't carry in vacuum, hence why her voice was coming through the radio instead. "Our ship was heavily damaged and… Well, we ended up here. I was going to send out a distress call, but we didn't get a warm welcome from your military."

Leo nodded. "So far, nothing good has come from aliens."

"We're not… Well, never mind, I'll explain later. We – oh, I didn't introduce you, did I?" Now the blue-purple woman seemed to be addressing the robot, which stayed still.

"This is Master Chief Petty Officer Sierra-117," Cortana said. "He's a Spartan, 2nd generation – a super-soldier." The robot made an abortive – or protesting – twitch. Or he was simply twitching. It was hard to tell.

Leo didn't know quite what to make of that, except that the robot was clearly military.

"And who are you?" Cortana asked kindly after a brief pause.

"I am Leonardo," Leo answered. He pointed to his brothers in turn. "Donatello, Michelangelo, and Raphael. We're brothers."

"Nice to meet you. As I was saying, we could use a lift back to Earth. This ship is coming apart at the seams, as you can tell."

"Well, it's your lucky day, Miss Glowy Person!" Mikey giggled, coming up the pedestal. "We've got an awesome spaceship, thanks to Donnie here." Mike made a move as if to give the woman his hand – Leo started to roll his eyes when suddenly, the robot moved and pushed the smaller turtle backwards, really hard. Mike hit the wall with a startled "Oof!" that came over the radio.

"Hey!" Raph protested, launching himself at the green robot just as Cortana yelled "No, stop!" over the speakers. Leo attacked with Raph – if the green robot had hurt Mikey, it was going down.

However, he had no katanas here, and the robot didn't seem to want to use its rifle, as it caught Raph's fist in one large hand and shoved him away, seemingly without effort. Leo tried a feint to the thing's right and kicked at its left knee, but the robot moved _way_ too fast and caught the kick. Instead of being thrown, though, Leo fell to the ground and the robot placed one boot on his plastron in a clear warning. He wasn't pushing down yet – but there was no doubt in Leo's mind that he could, if he wanted to, crush the turtle's bony chest.

"Stand down."

_That_ voice was definitely male and had tones of authority and power behind it. The green robot's head shifted to fix Raph, who was climbing back to his feet.

"Mike's fine," Don reported quietly over the radio.

"Sorry if I offended," Mike said, his voice small.

"No," Cortana sighed. There was frustration but subtle warmth behind her tone now. "We're too used to war, and no one grabs an AI like that. He'll let you up, Leo. Just please don't attack us again. You won't survive."

The green robot lifted his boot and resumed a silent stance next to the pedestal. He slung his rifle over his back and it stayed there, perhaps held by a magnet – Leo wasn't especially curious as Raph helped him to his feet.

Leo had the distinct impression that the green robot was talking to Cortana, because she turned towards it and then faced him again.

"If you would be so kind as to give us a ride down to Earth, we need to figure out some things," the AI continued.

Leo glanced at Don, who nodded slightly. "It would be rude of me to refuse," Leo said calmly and formally over the radio. "But we do ask that you stay with us. Our world is not used to dimension-hoppers."

"Agreed," Cortana said quickly. "We should get moving. He's only got enough air for a couple more hours, and I'd rather not test the suit's continued integrity after our last battle." She pointed at the green robot; it lifted its head slightly in either acknowledgement or disagreement.

"Is there… Someone inside there?" Don asked, leaning forward – looking but definitely not touching, after seeing the green thing take out three brothers in a few seconds.

"Yes," Cortana answered, a little snappishly. "He's not a robot."

_Well, that changes things_, Leo thought to himself, looking again at the suit of armor with new eyes. The human inside it was probably around seven feet tall. He didn't particularly want to see if ninjitsu or technology would win in a battle between him and the turtles.

"Is he – are you a human?" Don asked.

"So far as that classification goes," Cortana answered with a slight chuckle. "Though Spartans are… Well, kind of their own race."

"Can we please go?" Mikey whined. "I have a headache."

"Sorry about that," Cortana said. "Just a moment; I need to transfer into the Chief's suit and then we can leave."

The green man – "the Chief", apparently, though it – he – had been introduced as "Master Chief Petty Officer Sierra-117" – placed an armored glove on the pedestal and the lady vanished. The suit of armor was still for a moment, then moved forward with a quick pace.

"Uh, shouldn't we be leading?" Don muttered over the radio to Leo as they followed the massive giant out of the control room and back towards the turtle's spacecraft.

"We saw you come in the landing bay," Cortana answered over the radio.

"You can still talk to us?"

"Of course," she said smugly. "The MJOLNIR armor is equipped with excellent comms, and your radio is not _too_ far behind ours. It's rather advanced, really, for your period."

"Don's a genius," Mike chuckled.

Then they got to the spaceship, the green giant actually halted for a moment.

"That is the… most unique spaceship I've ever seen," Cortana murmured into all their radios.

"It's the SpaceShell!" Mike told her, as proud as though he'd built it. "I named it. Don built it."

Looking at it through a stranger's eyes, Leo could understand Cortana's surprise. The ship was slightly larger than a Semi-truck, after the initial boosters had fallen off, and painted green. Don had designed the landing pieces to look kind of like turtle feet, and the top of the ship had a definite shell shape to it. Leo activated the door mechanism and waved everyone inside.

It was cramped even with the armored guy crouched in a corner, as far out of the way as possible. Don wiggled into his pilot's seat and Leo shut the door, pressing the buttons in the "seal" sequence Don had showed him. The cabin pressurized and Don removed his helmet immediately, swinging around to face the green armor.

"You're not human." Now Cortana's voice was coming from two smallish projections on either side of the armor's helmet.

"No," Don answered, shaking his head. "We're terrapins – mutant turtles, really. Hence "SpaceShell," courtesy of Mikey."

Leo removed his own helmet and then climbed out of the bulky spacesuit. The soldier's head turned towards him. "I see what you mean by mutant," Cortana said after a second. "Most interesting. I would love to – oh, we don't have the med lab anymore." She sounded mildly disappointed.

"I'd be happy to share notes and stuff with you," Don said quickly. "With your knowledge of advanced technology, maybe you could help me figure out some anomalies I've found."

"I'd be delighted." _Now_ Cortana sounded like Don, excited by the possibility of sitting in front of a computer reading numbers for who knows how long.

"Let's get going," Leo suggested, slipping into his seat and buckling in. Mikey was already in his seat and trying to wiggle out of his spacesuit without undoing the five-point harness.

"Yer an idiot, Mikey," Raph grumbled as he stripped off his own suit and sat down at the weapons panel. He covertly glared at the green soldier, but either the man was ignoring Leo's brother or didn't notice.

"So, remind me of your names, now that I can attach them to faces?" Cortana asked politely as the ship lifted away from the wreckage.

"Leo," the oldest turtle said, pointing to the blue mask. "Our masks identify us, because we're pretty similar without them. I'm blue, Raph's red, Mikey's orange, and Don's purple."

"And you live on Earth?" Cortana asked. "If I may ask, how did you become mutated?"

This, of course, sparked a quick history told by Don, who emphasized the scientific aspects, and pretty soon, Leo tuned the conversation out as his brother and the AI started chattering in what could have been a completely alien language for all the eldest understood it.

Mikey had fallen asleep, as he was wont to do, and Raph was still glaring holes in the suit, so Leo turned his focus inwards and meditated. It would be a few hours before they got home, and he wasn't looking forward to explaining their visitors to Splinter.

_~~CROSSOVER~~_

John let Cortana have free reign of his loudspeakers and leaned back against the cramped ship's bulkhead, studying the creature in front of him. Donatello, or Don, was his name, and he kind of looked like a shell-backed Jackal, except blockier and greener.

The creature had three toes and fingers on each hand and foot, two arms and two legs, with basic human-like joints. The torso was where it got really weird; instead of a chest, stomach, and back, the turtle had a hard shell. Don could sit up straight only because the seat had a slight depression into which his shell fit. His skin was a slightly lighter shade of green than Leo's, which was slightly lighter than Mikey's, and Raph's skin was the darkest green. The creatures all had blunt heads with hairless scalps – they were reptilian, after all – and large noses that doubled as a soft beak.

John turned on his posterior camera and saw that Raph was still glaring at him. He probably shouldn't have reacted so badly to the orange one trying to grab Cortana – he couldn't do her avatar any harm, after all – but it had been instinct and reflex.

John's stomach grumbled and reminded him that it had been several hours before entering cryo and three years since he'd last eaten. The nutrient paste from the cryotube had sustained minimal life, just enough to avoid true death, but the solder was _hungry_. Hopefully the turtles ate something like human food, and would have some when they landed.

"Dudes, I'm hungry," the smallest – standing at 5'3" – said with a definite whine in his voice. Mikey seemed to be a happy-go-lucky personality, though John noticed he avoided getting too close to the soldier after his initial slap on the wrist. Really, John had been very careful not to injure the smaller humanoid when defending Cortana back on the _Dawn_.

Leo, who had been sitting the past hour with his eyes closed, cracked open one eye and sighed slightly. "Mikey, we'll be home soon."

"My stomach requires sustenance!" the orange-masked turtle announced importantly.

"Ya could burn some of that baby fat, little bro," Raph snickered. "Now shut up and go back to sleep."

"Meanie," Mikey pouted, crossing his arms.

John shook his head slightly; these turtles were clearly civilians, and it had been a long time since the Spartan had spent time around civilians. He was used – had been used, he reminded himself – to the discipline and order of his Spartans, which surpassed even that of the military.

"Sooooo…" Mikey was apparently looking for something to do and his eyes latched on John's visor, though making eye-contact through it was nearly impossible for someone on the outside. "We can't call ya "Master Chief Petty Officer Sierra-117" every time we're talkin' to ya, so what's yer name?" he asked, grinning. It was a simple question, but one that John wasn't used to getting.

Cortana paused in her discussion with Don to allow John use of the loudspeakers to answer. He thought for a moment, then answered, "Call me Chief."

"John," Cortana scolded inside the confines of his helmet. She appeared on his HUD. "They could use a real name. It's not like you have an identity to hide here, and there _is_ no UNSC protocol."

"When can we expect to return to our universe?" John asked simply, ignoring Cortana's frustrated shake of the head on his HUD.

"I don't know," she replied. "Probably not for a while; we need to patch you up, and then patch the ship up, and these guys don't have the right tech for that… Though I get the feeling they have some space-going friends who may be able to help. Don and I are discussing the possibilities, if you want to listen in."

"I probably won't understand more than half of it," John reminded the AI.

"Well, no," she admitted. "But it's better than listening to your stomach growl."

"Touché," John muttered. He turned his attention back to Mikey.

"Chief is a cool name," the terrapin had been saying. "So, are you, like, chief of some tribe or something? Is everyone where you come from as big as you? Do you all wear armor? Oooo, could I get some?!" That seemed to excite the turtle as he bounced in his seat.

"No, no, no, and no," John replied coolly.

"Where _do_ you come from?" Don asked before Mikey could whine in protest.

"Our universe is a version of yours, but 500 years in the future," Cortana answered. She explained about the United Earth Government, the expansion of humanity to Mars and then other solar systems, and then with she and Don were off again, discussing Slipspace trajectories and theories.

The ship shook around them some time later as they re-entered atmosphere and Don turned his full attention to piloting the unwieldy SpaceShell, leaving Cortana free to talk with John. She had, out of courtesy, _not_ tapped into the ship's external cameras, so she couldn't see where they were landing.

"Brace yourselves," Don said calmly as the ship glided into a more level flight. "We'll be going underwater soon."

"Do you live underwater?" Cortana asked, seizing the opportunity to find out more about their host.

"No," Don chuckled, "we live in the sewers of New York City, in America."

Cortana hummed thoughtfully. "We have a United Republic of North America, part of which used to be the United States of America – is that what you mean?"

"Yes," Don answered, tilting his head thoughtfully.

"And you live in the sewers? I gathered from your original warning that aliens are not welcome that the general population is unwelcoming, but does this mean you four are _also_ in hiding?"

"Exactly," Leo answered. "The humans don't like monsters – as they see us. So we don't go out in daylight, and we live in the sewers."

"We have a few human friends," Mikey said excitedly. "People we've rescued from the Foot, or who've gotten lost in the sewers."

"The Foot?" Cortana asked, emphasizing the capital letter.

"A bunch of evil ninjas," Mike explained unhelpfully.

"They used to be led by Master Shredder, a reincarnation of an ancient evil in Japan, but we defeated him last year and his clan – the Foot – are now led by his daughter, Karai." Leo's tone was hard and unforgiving; clearly it was not a comfortable topic. "She has vowed to kill us in revenge, and in the meantime, is trying to rebuild her father's criminal empire in New York City."

John was slightly confused – what were ninjas? – but got the main idea. As unprofessional as they were, these four brothers were clearly some sort of soldier, and definitely involved in a war. Perhaps not a high-tech one, judging by the "ship" they were in, but a war nonetheless.

_~~CROSSOVER~~_

Don guided the ship down into the water with hardly a splash and they sank quickly towards the bottom of the ocean. He pressed the garage's underwater door opener and part of the seabed retracted, allowing him to pilot the SpaceShell through the tunnel and into the main docking bay underneath the lair. The then shut the outer door and initiated the pumps that would empty the room of water.

"Dudes, let's go!" Mikey called urgently. "I gotta _go_, Donnie."

Donnie shook his head slightly. "You should have gone before we left," he admonished.

"I did!"

"No, ya didn't," Raph growled. "Ya went to yer room and read comics for an hour. Ah had t' drag ya outta there and into the ship."

"Well, I went before _that_," Mikey said, wiggling out of his seat. "Come _on_, Donnie, open it! A turtle needs to go!"

Don pressed the door mechanism and it slowly opened; the bay was not yet empty of water, but Mikey swam towards the elevator anyway.

"Don't pee in the pool!" he giggled as he pressed the elevator's call key. The youngest disappeared into the elevator with quite a bit of water and headed up – thankfully, Don had drilled drainage holes into the bottom plate of the elevator so Mikey wouldn't flood the lair with seawater when the door opened upstairs.

The Chief was the next one out of the ship, as he was closer to the door than Don, Raph, and Leo, and landed in the water with a quiet metallic thunk from his boots. He walked through the four-foot-deep lake without apparent difficulty towards where Mikey had disappeared.

Don, Leo, and Raph hurried out of the ship as well and, as the water was only three feet by the time all three were out, half-swam, half-walked over to the elevator. "The stairs are over here," Leo said by way of invitation.

Chief surveyed them silently, then Cortana asked, "Out of curiosity, how much weight can those stairs handle?"

Don blinked, then tilted his head. "I designed them for a maximum load of five hundred pounds, on any single step. The elevator can carry two thousand pounds. It was overkill, but I had to get some equipment back and forth."

"We'll wait for the elevator," Cortana chuckled. "With the armor, the Chief weighs a good 1300 pounds."

Don whistled. "Well, um, if you don't mind, could I maybe wait with you? I'd like to show you how the elevator works so you can move around as you please," he said, addressing Chief.

"Thank you," the man said quietly. He didn't seem to speak much so Don appreciated the acknowledgment. There was something decidedly inhuman about the green armor.

"I'll go tell Master Splinter we have guests," Leo told Don, motioning for Raph to join them as he climbed up the steps.

"Will you need to remove your armor to repair it?" Don asked once the three – Chief, Cortana, and he – were alone.

"Yes," the Chief answered.

"Do you – that is, would you like my help?"

"It would be appreciated."

"And I can tell you what we need to repair it, and how to do it, if you'd like to help me work on it," Cortana added.

Don grinned widely. "I would love that," he admitted.

The elevator dinged as it opened; Don stepped in and slightly to one side to make room for the large Chief. Even standing in the middle of the vaguely egg-shaped room, the Chief had to duck.

"I didn't build it with people your size in mind," Don admitted ruefully, punching the main floor button. "These buttons take you to the garage – where we just were – the lair, and up top, or street side, as we call it." He pointed to the buttons in order.

The Chief nodded slightly. "We've got a guest room you can use for as long as you need," the turtle continued as the doors slid shut.

"Do you, by chance, have a computer I could transfer into? Once the Chief powers the suit down, I'll need somewhere to go or I'll hibernate, and this is too exciting for that," Cortana chuckled.

"Sure, I have a main control center you could probably use, I think. How do you move around?"

"My central data chip is stored in the Chief's helmet, but I can remotely jump through his suit."

"Cool," Don murmured. The elevator dinged as it arrived in the lower level of the lair; Don motioned for the Chief to step out first.

The Chief did so and then stopped suddenly; Don stepped around him to find Master Splinter waiting, tapping his tail thoughtfully against the floor as he studied the giant green suit of armor.

Leo was standing just behind Master Splinter; Mike and Raph were probably getting the guest room ready. Master Splinter nodded a polite greeting; the Chief inclined his head.

"Hello," Master Splinter said formally. "I am Master Splinter."

"It is an honor," Cortana answered formally. "I am Cortana, and the suit of armor is the Chief."

Clearly Leo had explained a little bit about the woman apparently living in a suit of armor with the Chief, because Master Splinter simply nodded slightly. "Welcome to our home," he said. "Leonardo has told me something of your tale, but I am intrigued to hear more, once you have refreshed yourselves. My sons will show you the lair." He turned; Don and Leo bowed slightly as he walked his slow but steady way back into his room.

"What would you like to see first?" Leo asked. "I could give you the grand tour, or we could show you to your room if you'd like to get changed first."

"I would love to get out of the suit's systems," Cortana admitted.

Don grinned slightly. "If you'll follow me, ma'am, sir," he said, bowing elegantly towards his lab with a flourish. He led the way into the lab and pointed out the kitchen on the way over.

"And this is where the magic happens," he said, opening the doors to his personal lab. "Or, at least, the science."

The room seemed smaller once the Chief stepped inside, but Don had enough room to move around him. "Over here is my main computer terminal. I don't know what sort of chip you have…"

"Basic memory chip," Cortana answered. "I can integrate through the suit, though, no worries."

The Chief laid a very gentle hand on one of the main servers and then pulled it back after a moment of silence.

The main computer screen flickered to life and Cortana's face appeared on it. "2D graphics," she sighed. "Makes a girl feel flat."

Don grinned apologetically. "I haven't quite gotten a hologram projector small enough to fit on a desk to work yet, but maybe with your help…" He raised an eyeridge slightly in invitation.

"I'm sure we can come up with something," Cortana assured him. "Your systems are… hm, archaic by our standards, but functional." Don nodded, slightly injured – his computers were far better than anything else on the planet, thanks to a combination of Atlantian and Utrom technology. "My, my, how interesting…"

Clearly, Cortana was rooting around in the files left on his harddrive, but Don didn't mind. He turned instead to the Chief. "And how can I help you?" he asked eagerly.

"We'll need to get him out of the armor first," Cortana answered as the Chief reached up behind him and unlatched the large rifle from his back. Don indicated a clear table – well, he cleared it quickly, anyway – for the weapon.

"Do you need special tools?"

"We carry them with us, now, a hand-held set, in case of emergency field repairs. Chief?"

The Chief tapped a thigh pocket and it opened; he handed a small metal box to Don, who grinned in delight. This was going to be _fun_.

There was a pneumatic hiss from the neck of the suit of armor, and the Chief pulled his helmet off smoothly. Don studied his face for a moment, quietly shocked. The man's brown hair was a strict buzz-cut, darkened with sweat and blood. His face was unnaturally pale, though he didn't look particularly ill, and his pupils were larger than normal even as they shrank under the direct light from the ceiling's panels. The irises around his black pupils were a dark blue color, and one eye was bloodshot. There was also a black band around the irises.

A purpling bruise on the same side of his cheekbone said something had hit him – hard, through the helmet – and left its mark. His chin was covered with a few days' stubbly growth. And his entire face was covered – literally covered – in scars. There were several that were surgically precise, but many more were ragged. Don couldn't identify the sources for most of them.

The Chief set his helmet down on the table gently, and then motioned to the box Don was holding. "It will break down into the wrenches I need," he explained, twisting his left wrist in his right hand and unsealing the glove on that side. He placed both gloves next to the helmet, revealing thick but nimble – and, again, scarred – hands.

Don set the box on the table and found the opening latch. It was fairly self-explanatory, though Cortana offered a few hints, following their progress through three web-cams Don dug out from under a pile of books at the AI's request.

"Forearms first," the Chief said, holding his arms out to his sides.

Don looked up and then grinned slightly. "I'm going to need a stepladder," he said. "Be right back!"

He ran out into the main lair and found Raph, who was using the stepladder to dust the lights in the guestroom.

"Wanna help me get the Chief out of his armor?" Don asked.

"Do you have any idea what that sounded like?" Raph grumped.

Don rolled his eyes. "I could use an extra pair of hands, and Mikey wouldn't be at all helpful."

"Fine." Raph folded the stepladder and followed Don back to the lab, where they found the Chief standing quite still as Mikey sat sideways on his right shoulder, using the tools Don had _carefully_ put back into place to unscrew something in the armor's elbow joint as the man held it out to his side.

"Oh, hey, Donnie!" Mikey called as they entered. "Check it out, I'm an engineer!" He waved the wrench.

"Careful with that," Don snapped.

"He couldn't break it if he tried," Cortana chuckled. "Actually, this is rather amusing."

"This is _Mikey_ we're talking about," Don told the AI. "He breaks toasters by looking at them." Raph set the stepladder down and Don climbed to the upper rung, which put him at a good level to be working on the Chief's armor.

The forearm armor suddenly unlatched and Don caught it just as Mikey yelped with the sudden change. With a glare for the youngest, Don lowered the armor – it was much heavier than it looked, and just peeking at the integrated circuitry and gel layer made the brainiac drool – to Raph, who set it on the table.

"The shoulder joint had two bolts," the Chief said calmly. His forearm was encased in a black skin-tight suit, through which several wires ran that Don could barely see. The man's forearm was as thick around as Don's not-insubstantial calf.

"Damn, dude. How do you get out of this thing yourself?" Mikey grunted, going to work on the next set of bolts.

"Each Spartan is assigned a team of technicians – or rather, our armor is," the Chief answered. "They are responsible for the maintenance and repair, as well as getting us in and out of it, should the situation demand it."

"Us?" Don asked, curious, as he pointed Mikey to the second bolt.

Brief pain flashed behind the man's suddenly-guarded eyes, and Don knew he had asked a sensitive question. "My fellow Spartans and I," he answered shortly.

"There were originally thirty-three Spartan-IIs," Cortana explained from the computer's speakers. Did Don imagine it, or did the Chief flinch ever so slightly? "The Chief is the only one still alive that we know of."

"What happened to the rest?" Mikey asked. Typical, insensitive – or ignorant – Mikey. Don shook his head, but Cortana's avatar merely smiled sadly.

"They did what they do best – they protected humanity from some of the worst aliens you can imagine."

The shoulder armor clanked open and Don caught it, handing it off to Raph. The Chief rotated his arm a couple of times and then held the other one out; Mikey moved over quickly and Don moved his stepladder.

"If I may ask, what kind of aliens?" Don asked Cortana, sensing the Chief wasn't going to talk about it.

"The Covenant is a group of alien races. They are led by a race we call Prophets – grey humanoids with long necks and short bodies, which usually float around on gravity belts. Their main warriors are Elites, three-meter-tall humanoids with a vicious sense of honor and excellent fighting skills, Jackals, vulture-like aliens with shielding technology and usually found in three-packs, and Grunts, the cannon-fodder. Then there are Brutes and Hunters, not to mention the Bugs, but they're rarer. Their mission is to follow the Forerunners on a Great Journey – it's a religion, and part of that religion was, until recently, "kill all humans." They wiped out billions of us… And when we were lost in space, the war was still going on." There was decided sadness in Cortana's voice.

"We lost entire planets – they come in, take the planet, and then glass it from orbit. They pour heated plasma onto a planet's surface and slag it until nothing can live on it for a few centuries. The Spartans have been instrumental in leading offensive missions onto Covenant ships and even homeworlds, and the Chief and I were part of a team that prevented the Covenant from firing a Halo, which would wipe out all sentient life within a few thousand light-years."

Don whistled as he handed the Chief's shoulder armor to Raph, to join the three other pieces of armor they had removed. Mikey gracefully jumped down from the man's shoulders.

"So it is imperative we return to our universe as quickly as possible," Cortana continued. "Now, the chest piece has bolts all along the right side – yes, there – and comes apart in two pieces."

Don and Raph braced the back piece as Mikey attacked the bolts and the Chief held the front piece. The whole thing came off quickly; the Chief held the chest piece as though it weighed nothing though Don and Raph swore in unison as the back piece fell into their waiting arms. Beneath it, the armor extended in a sci-fi-like projection up from the armor at the base of his spine to the bottom of his skull, where Don noticed a small port. The Chief reached back calmly and detached the wire.

"How do you walk around in this stuff?" Raph grunted unhappily. He and Don set the piece down on the floor – gently, even if they couldn't dent the armor. The Chief set the chest piece next to it.

"It takes getting used to," the man said quietly. "But I've worn it – and other versions – for thirty years."

"You look young for someone who's fought for thirty years," Mikey chuckled.

The Chief merely nodded quietly.

"Hey, Don, I… Oh, sorry," Leo said, coming into the lab. He glanced between the half-unarmored Chief and the pile of armor sitting to his left. "How's it going in here?" he asked instead.

"We're about half-way done," Don reported, grinning. "I think the hardest part is done."

"Is there anything I can do to help?"

"You, Butterfingers McClumsy?" Mikey scoffed good-naturedly.

"I resent that," Leo muttered.

"No, you _resemble_ it," Raph teased, grinning slightly. "He's right, you're clumsy."

"I think we've got it, but Chief'd be the one to ask."

"It shouldn't take more than two people to get the rest," Cortana answered instead. "If you need Don for something, I can direct Raph and Mikey."

There was a look of "oh, God, no," that briefly flashed over the Chief's face as he glanced at Cortana's avatar. Leo grinned slightly. "No, nothing important, carry on." He was rather intrigued, however, and leaned against a wall to stay out of the way and observe.

"Alright, Mikey, left hip first," Cortana ordered. Mikey set about unbolting that section while Don and Raph stood by to catch the armor. When he had it unbolted, however, instead of falling off, the Chief gently took the wrench back and expertly unbolted three hidden bolts at the front of the main leg pieces and then Cortana showed Mikey how to do the same on the back panel.

"These pieces slide off," Cortana explained. "So we have to loosen everything and then he basically wiggles out. We usually have a crane for lifting them in and out, but we can make do."

Don nodded in understanding and they set to loosening all the bolts. The boots were the hardest part, consisting of several smaller pieces that had to be individually loosened with separate tools from the box the Chief had provided.

However, it was finally done and the Chief wiggled experimentally, then carefully pulled first his right and then his left leg out of the armor. It stood upright without him in it, and Don shook his head in amazement.

The Chief was dressed in nothing more than a skin-tight suit, black in color, which covered him from the base of his chin to his wrists and ankles. He was unnaturally pale where his skin did show, and all four turtles noted silently the scars crisscrossing those spots.

"What's the suit for?" Mikey asked, poking at the legs of armor.

"Armor integration," Cortana answered. "It allows me to monitor the Chief's vitals, inject biofoam, control the suit's internal temperature."

"Seeing you outside your armor, I don't know if we have clothing that will fit you," Leo admitted with a slight chuckled. "Casey – a human friend of ours – is half your size."

The Chief nodded slightly in understanding. Though the UNSC now carried Spartan-sized clothing, the first few months had been a game of "how small can you be?" when getting into fatigues.

"Let me call April; she'll bring something by." Leo disappeared before the Chief could protest that he didn't want to intrude so far on their hospitality, but Cortana nodded.

"You can't wander around in just the suit, Chief," she told him, grinning.

The Chief nodded reluctantly in agreement and carefully stacked the leg armor with the chest pieces on the floor below the table. Don turned to the computer and Cortana, addressing her directly as Raph and Mikey, after a smack from the hothead, left the three to begin the repair process.

_~~CROSSOVER~~_

"We should run a full diagnostic first," Cortana mused. "I don't know how much of a beating you took, Chief, that last run."

John nodded thoughtfully, fitting the armor together again and laying it out on the lab floor for lack of a stand. Don watched covertly, clearly a quick learner; when John looked around for the wrench set he had brought along, Don handed it over with a slight grin. The Spartan nodded his thanks and, probably at Cortana's gentle hints, showed Don how to run the diagnostic software using the helmet's built-in controls, which were set so he could use his chin to activate them.

"The diagnostic will run in the background," Cortana told the pair. "I'll watch it. Donatello, if you like, I could improve on some of your coding for the patches from the suit to your computer, if that's okay with you."

"Improve away!" Don said immediately, grinning slightly. "I'd love to see what you come up with, if that's okay."

"Of course."

John stood and left the two speaking rapidly in terms he recalled vaguely from his lessons in engineering and computer software, but had mostly forgotten. Stepping out of the lab, he nearly stepped _on_ Mikey.

"Hey, dude, com'on, I'll give you the tour!" the exuberant turtle said, gesturing for John to follow.

The Chief simply nodded and followed the hyper turtle. He was introduced again to the kitchen and given full reign – he knew he'd be using it, though Mikey had already made some sort of food and offered him a PB&J sandwich, made with peanut butter, raspberry and strawberry jams, and whole wheat toast. It was possibly the most sugary and flavorful thing John had eaten since his augmentations and it was a battle to keep it in his soldier's stomach as they wandered through the rest of the lair.

"This is the dojo," Mikey said after pointing out the bathroom on this level, which included a shower, and the living room. "We only go in to train, and, well, it's kind of off-limits to guests." He smiled apologetically. John simply nodded in understanding.

"And this is Master Splinter's room, and this is the linen closet – if you need blankets or sheets or something, they're in here." Mikey then led him up the stairs. "And this is Leo's room." The faint scent of incense leaked from it, much as it did from Master Splinter's room. "This is Raph's." Even through the thick door, John could hear the sound of loud rock-'n'-roll music blaring in the background and the thud of something heavy being hit. "They stay in their rooms a lot. Leo meditates, Raph goes Hulk on his punching bag." Mikey grinned, inviting the Spartan to share the joke. John felt the corner of his lip tug upward slightly; something about Mikey's innocence and honest goodwill was intoxicating to the veteran soldier.

"Anyway. This is my room, and this is Don's. I have a bunch of comics – feel free to borrow them if you treat 'em nice! They're my babies." Mikey's room, when he opened the door, looked like a minor hurricane had come through recently. John detected the faint whiff of old food and sweat. "There's a bathroom up here, and a shower, so the one downstairs is all yours!"

"Thank you," John said quietly.

"No problem. Hey, you ever played video games?"

John shook his head slightly. "Simulations, yes," he answered.

Mikey gaped and then grabbed John's hand with a speed that could have rivaled Kelly's and launched himself down towards the lower level of the lair. There was no way John was following that way, so he simply twisted his wrist, making Mikey's grip loosen, and calmly walked down the stairs.

"You're no fun," the turtle pouted once the Spartan rejoined him on the bottom floor. "We always jump down, and sometimes flip up. That way, we keep up with our trainin'. Come on, over here."

Mikey explained the controller to the game box called an X-Box 360, whatever that meant, and called up a 2D video game. It was a simple racing game, he'd said, but when the turtle was picking his character, John couldn't recognize any of the cars or characters.

"There, your turn!"

John decided to humor the young-sounding turtle and folded himself carefully next to the sofa. "Dude, you _could_ sit next to me. I don't bite. Hard." Mikey grinned and waggled his eyeridges up and down rapidly.

"The floor is comfortable," John replied, though honestly, he didn't trust the rickety thing to bear up under his substantial weight.

"Alright, your choice, dude. Okay, pick your character. Joystick over to the right… There you go!"

John's hands were much too big for the tiny controller, and he reminded himself _not_ to hold it too firmly, but he gently maneuvered his thumb around until he had chosen a turtle character with spikes on his shell.

"Alright, let's do this!" Mikey crowed. He sounded way too excited for a simple game. John saw his car was the focus of the half of the TV directly in front of him and pressed the button Mikey had pointed out as the gas pedal. The count-down timer finished and his car shot out from behind the checkered starting line; John jigged his thumb left and made the first turn before something large, yellow, and glowing appeared in front of him and he dodged it.

"No, hit those!" Mikey yelled at entirely too loud a volume for the quiet living room. "They're power-ups."

John nodded and hit the next glowing thing. "Alright, now activate it with this button," Mikey said, leaning over John's shoulder to show him. "There you go! Except you're in first place, so that was kind of useless…"

John simply nodded and drifted his car around another turn. He slipped in a puddle of oil and the car slid sideways, but he quickly righted it and shot ahead again.

"Dude, you're fearless!" Mikey laughed. "Take that!"

John's car suddenly flipped end-over-end and landed on its head; expecting it to be over, John set his controller aside.

"Dude, no, you respawn – pick your controller up!"

John did as Mikey told him to and his car, sure enough, was on the track again. He pressed the gas button and shot back into the race, but was now in third place. The power-up activation button did nothing – perhaps it only worked once – so he set out on ramming the car in front of him.

He spun the green alligator-dinosaur off the edge of a rainbow-colored bridge and then smashed a little mushroom-looking thing into a pylon and left it to respawn. Now Mikey was in the lead, and John planned to catch up.

John sped around the corners in the race with reckless speed, only missing the turn and flying off the edge once. Mikey, however, stayed elusively ahead of him.

"Dude, you're totally nuts," Mikey laughed when the race ended and he had won. He did a "victory dance" in front of the TV, to John's private amusement, which consisted mostly of hooting like a green Marine with his first Grunt kill.

"Mikey, _enough_ already," Leo groaned from the top of the stairs, coming down. "I see Mikey has shown you the wonders of Mario Kart."

John assumed this was addressed to him and nodded, reminding himself to smile slightly. Leo sat gracefully down in an armchair to John's left and held up a long black object, which he pointed at the TV. It changed the input, apparently, as the race's stats disappeared – much to Mikey's apparent dismay – and instead a news report came on instead.

"Sources within Syria say that the chemical weapons were not released by the Syrian government but were the work of the terrorists and rebels."

John listened intently as the woman on the screen described a chemical weapon's release in a country called Syria. Leo shook his head in mute sadness and anger as pictures of the deceased, mostly wrapped in white cloth, were shown.

"It seems that your world has its own problems," John said quietly when a group of scantily-glad men and women danced across the screen holding beers of a popular brand, obviously an advertisement.

"Not on such a large scale as yours, but yes, we have our wars," Leo said, shaking his head.

John was silent. If this world followed the same historical path as his Earth had, there would be worse in the future.

"Hey, guys, I'm here!" a decidedly feminine voice suddenly called from the elevator.

_~~CROSSOVER~~_

April wasn't sure why Leo wanted XXXL shirts and pants – and underwear – but figured it was probably something for Mikey, who had odd requests like this. So she bought three sets of clothing, in neutral grey and white tones at Leo's request, and hurried to the lair to find out what was going on.

Casey had come with her. With the recent political upheaval, criminals were finding it easier to escape over-worked cops and had upped the possibility of running into bad news when finding a sewer entrance in a dark alley.

The clothing was in a bag over Casey's shoulder – his rather amusing offer to "unburden the dame of her burden" being graciously accepted for the honest attempt at helpfulness it had been – and April stepped out of the elevator and into the lair quickly.

"Hey, April," Mikey yelled, catching the woman's immediate attention. She accepted his rather enthusiastic hug and then bowed slightly as Leo came over as well. Alerted by Mikey's shout, Don came out of his lab holding several pieces of wire, waved excitedly – April sensed he was onto something wonderful and would fill her in – and disappeared back inside.

"Hey, Casey!" Mikey was just as enthusiastic about hugging the large man and pulled on the bag around his shoulders. "Oooo, are these the clothes?"

Without waiting for an answer, he turned and ran back towards the living room. "Hey, Chief, here ya go!"

_That_ was when a very large, bulky man stood from the floor near the couch. April nearly did a triple-take after the first double-take. The man was easily seven feet tall and dressed in a skin-tight – and form-fitting, she noticed with a faint blush, though of course the turtles hadn't thought much of it – black suit. His hair was cut very short, a dark brown or black in color, and he had a large purple bruise on one cheekbone. He was unnaturally pale. The whole package _screamed_ "dangerous."

Mikey didn't bowl into the man as April expected, considering the youngest turtle's exuberance, but handed over the bag. The man tucked it under one arm and carefully made his way over towards April and Casey.

"Holy shit," Casey muttered quietly from behind her. He was even bigger up-close.

"Thank you," the man said quietly. His voice was slightly hoarse and very deep. He inclined his head politely.

"Oh, uh, you're welcome," April stammered, looking away from his piercing gaze. Up close, she noticed all the scars across his face and his blue eyes that stared – not rudely, simply as though the man was used to maintaining eye contact – through her.

"Chief, this is April O'Neal and Casey Jones," Leo said formally. "April, Casey, this is… the Chief."

"UNSC Master Chief Petty Officer Sierra-117, Spartan II, at your service," the tall man said quietly. He nearly struck a salute and then seemed to think better of it and held out a hand with the awkwardness of someone less used to friendly greetings.

"It's lovely to meet you," April answered, shaking his hand. His grip was surprisingly gentle, though there was solid strength in those fingers even as he released her hand.

"That's a mouthful," Casey grunted. "Call me Casey," he instructed, shaking his hand – and clearly trying to intimidate him, though the taller, broader, and more muscular man didn't seem fazed.

"Most call me Chief," the Chief admitted.

Casey was discreetly trying to shake his hand out when Mikey lead the Chief away towards the guest room's shower, probably to clean up. From up close, April had recognized old blood dried into his hair and along his jawline.

"Who the hell is _that_?" Casey hissed when they heard the bathroom door shut.

Leo shrugged. "He and Cortana – an AI – showed up a couple days ago on Don's long-range scanners, out beyond Jupiter, and we went to figure out if it was Utrom or something coming towards Earth. We found them instead.

"The Chief's a Spartan – some sort of super-soldier – and they come from a universe where humanity is currently in the 26th century and has expanded beyond Earth, but ran into a bunch of aliens called the Covenant and have been fighting a losing war with them for thirty years. He's the last of his kind, been fighting for thirty years apparently. He was lost on their ship, the _Forward Unto Dawn_, with his AI companion and they've been drifting for three years. Then some sort of space-time anomaly brought them here – well, to our system, at least – and now they're trying to get home. If there is a home to go to."

"An AI?" That probably explained Don's simple greeting instead of his usual shy hug. "Is it with Don in the lab?"

"Should be." Leo waved her on, grinning. "He's been wanting to talk to you about it. None of us can understand their techno babble."

She certainly didn't need another invitation and set out for the lab at a brisk walk. She came in to find Don under a table, apparently chasing a screw, and a feminine voice saying, "Now, if you just – oh, hello."

Three webcams on Don's main computer desk swiveled to point towards April and the door and a blue female's face on the main computer screen drew April's attention. "I am Cortana," the blue figure said pleasantly.

"H-Hi," April said after a moment. "I'm April O'Neal."

Two of the webcams turned back around and April followed their "gaze" to see a pile of massive green armor laid out on the floor. It was dented and scratched and hooked up to a dozen machines around the room, it seemed.

"April, you have _got_ to see this!" Don told her from under the desk. "Cortana's showing me how to replicate the armor's gel layer right now, and we've just finished as holotank. Check it out!"

Apparently Don was searching among his dozens of power strips for a free plug, as he finally gave a pleased grunt and a small device on the table above him whirred to life. The blue face disappeared from the screen of the computer and, instead, a slightly blurry 3D figure – a blue-purple figure, naked except for lines of coding and with short purple hair – appeared.

"Adjusting focus," the figure said, its voice projecting tinnily from the speakers in the device's base. The hologram snapped into focus. "There we are. How do I look?"

"Very sharp," Don said, grinning at the half-foot-tall projection.

"Thank you for your help," Cortana said formally. She turned to April. "It is a pleasure, Miss O'Neal. I assume you've met the Chief already, because you seem to be taking my appearance in rather well." She chuckled warmly.

April smiled. "Yes, I've… been introduced. Is that armor his?" she asked, pointing to the pile on the floor.

Cortana's avatar nodded and then shrugged slightly. "It was beat up in our last fight, and Don is helping me repair it. The Chief and I will have to return to the _Dawn_ and begin patch-work as quickly as possible, though I understand atmospheric elevators have not yet been developed."

April shook her head wordlessly. "Hmm," the AI murmured. "That will pose a difficult problem. I – well, now, don't _you_ look spiffy."

April turned around to find herself nose-to-bellybutton with the Chief, who was now dressed in a white T-shirt that, despite its size, still managed to define the man's rock-hard abdomen and muscular build. He stepped back slightly and April, blushing hard, moved aside to let him into the room. He was wearing of pair of black slacks and white socks. Somehow, he managed to look like he had ironed the shirt and pants, even though he'd had hardly five minutes to shower and dress.

"You _do_ clean up well," Cortana continued, clearly teasing the man. The Chief silently shook his head, though whether in disagreement or amusement was unclear, and picked up the holographic device gently.

"You've got a new body," he said softly, putting it back down.

"Yeah, well, what can a girl say? Don helped me build it."

"How is the suit?" The man crouched next to the armor.

"Diagnostics are showing major damage," Cortana sighed. "We don't have the room or tools to make the outer pieces, but Don and I are developing more of the gel to replace what you lost. That last Brute you fought really did some damage to the hardware, but I think I can make it fully functional. We'll have to see someone planet-side before you go taking on Hunters hand-to-hand, though."

John nodded tightly and stood. "The right knee joint is sticking a little – I can take care of that if you and Don – and Miss O'Neal," he added, with a glance at April who was clearly reading some of John's notes avidly, "-want to continue with the more technical repairs."

"Sure," Cortana answered.

April looked over Don's shoulder as he showed her the gel layer's make-up. It was impressive stuff, clearly capable of insulating the wearer from heat, cold, and electric shock. John sat cross-legged by the joint he wanted to repair and had it taken apart within moments, checking each piece and seal.

_~~CROSSOVER~~_

Casey grumbled under his breath as he mounted the stairs and then pounded on Raph's door. The hothead yelled something that the man took as permission to enter and opened the door. Raph was paused in the midst of beating on the punching bag, his favorite rock band playing in the background.

"Hey, Case," he grunted. "Met our new guests?"

"Just the guy," Casey answered, closing the door flopping onto the weight bench. Raph turned the music down to conversational levels.

"Kind of intimidating, ain't he?" Raph sniggered.

Casey frowned. "Freakin' strong," he answered. "Kinda cold, though."

Raph nodded. "Yeah, well, I guess bein' a soldier fer thirty years'd do that to anyone, 'specially if what Cortana described was true." Raph explained quickly what Cortana had told them about the Covenant and its fighting classes, and the Spartan's endangered status.

Casey whistled through his teeth. "Well, now I kinda feel bad, yanno, 'cause here I was thinkin' he was movin' in on Ape…"

"Dude, April's totally yours," Raph told him, smacking him upside the head. "I don't think the Chief is lookin' to settle down – he's still got a war to fight, back in their universe."

Casey nodded. "Yanno, it's just, when you're big and bad and suddenly there's someone bigger and obviously badder…"

"Ya, you saw the scars?"

"Jesus, he looks like he's been worked over with a razor… Or a dozen."

"Donnie said some of it is definitely surgical. Can't ID some of the rest, though. Makes ya wonder if all'a him's like that and how he managed to stay together."

Raph idly traced the line of one of his own scars, a rather large one through the lip of his left plastron, up his shoulder, and into the shell. It had been a sword that he hadn't dodged in time; his plastron had saved him from being stuck through the heart.

"Anyway. You guys stayin' for dinner?"

"I don't think I could get Ape outta Don's lab now if I offered chocolate and wine."

"And strawberries, never forget those," Raph reminded him, punching the man lightly.

"Dude, where the hell am I gonna find strawberries this late in the season?"

"When is strawberry season?" Raph asked, blinking.

"Well, peak season's April to June, but you can find 'em late as November, which is next month."

Raph just stared for a moment then shook his head slowly. "If this is what girls do to you, I'm glad I'm a mutant."

"If you ever find a girl, and you make a mistake – or she's angry for whatever reason, or no reason at all – you'll quickly memorize schedules and her favorite things."

"Whatever," Raph grunted.

"Seriously."

There was a quiet knock on the door and Leo poked his head in. "We're about to have dinner, if you're interested," he told the pair.

"Comin'," Raph replied, tossing his gloves into a corner. He wiped what sweat hadn't dried from his shoulders and followed Casey out of the room. They found everyone sitting in the living room – not only did the dining room table not have enough space, but the chairs would likely not hold the massive Chief for long.

Even Cortana was in attendance, her holotank plugged into the wall and sitting next to the Chief, who was seated, his back rim-rod straight, on the floor with his legs crossed in front of him and his hands resting easily on his knees. Even sitting, he came to the turtles' chests.

April invited Casey to sit next to her with a smile and then turned back to talking to Don avidly, something about elevators. Raph flopped into his customary seat on the couch on Don's other side, while Leo and Master Splinter were quietly engaging the Chief in a conversation about ninjitsu.

Mikey appeared with TV trays for everyone and then disappeared again, but not for long. Casey barely managed to surreptitiously wind his arm around April's shoulders with a glance at the Chief, who was apparently absorbed in the conversation with Master Splinter, before Mikey popped back out of the kitchen again with a big bowl of spaghetti with meat sauce – and veggie sauce for April, who was going vegetarian – and a side of stir-fried vegetables for everyone.

"Bon appetite!" Mikey told everyone. "Plenty of seconds."

_~~CROSSOVER~~_

Cortana watched the scene through the cameras now installed in the living room for her by a thoughtful Don as the humans and turtles around her set to the food with a will. She had managed to convey to Don the appetite of Spartans, and the type of food he was used to – or rather, the lack of it, considering their three years in space - which had prompted the turtle to tell Mikey that the youngest turtle's plans for an elaborate feast would likely be lost on the Spartan's stomach.

However, the slight shock and then growing pleasure on John's face more than made up for the simplicity of the fare. It was very subtle, but Cortana had learned to read the man's expressions to a tick.

Still, though the Chief was clearly making an effort not to inhale the food and to answer Master Splinter and Leo's questions truthfully, he was not a skilled conversationalist and he _was_ hungry, so he finished his first plate long before anyone else had, even if Mikey seemed to be racing him.

"Dude, how do you _do_ that?" Mikey gasped, holding a hand to his chest. Everyone turned to look at the youngest, while John tilted his head in confusion. "Eat so quickly. I was tryin' to keep pace, yanno, and I think I swallowed my fork."

The Chief shrugged slightly and Cortana wished his childhood lessons had included the art of eating slowly, at least when the situation called for it. "War zone meals are generally short," Cortana answered instead, trying to excuse her friend's lack of manners. "Don't want to be caught mid-chew when the Covenant storms your position."

"Riiiiight," Mikey agreed, nodding. "Makes sense. Want some more?"

John smiled briefly, his expression more open than Cortana had seen since the news of his last sibling's disappearance. "I can get it, thank you" he said quietly. "You should be regurgitating your fork."

Everyone was silent in shock for a moment, but John was already through the doorway in to the kitchen before Mikey blinked. "Wait, that was a joke. Dude, he cracked a joke!" He looked at Cortana excitedly. "I thought he was a Grumpy McGrumpPants."

Cortana giggled at the nickname. "The Chief can have his moments," she told the youngest brother.

"You cracked a joke," Mikey told John proudly as the giant man rejoined them and sat placidly back in his seat. The Spartan simply nodded, though there was a twinkle in the man's eyes that Cortana was glad to see.

Towards the end of the war, as it was becoming increasingly apparent that humanity was fighting a losing war, she and John had been shuttled back and forth with no regard for his very human need for real rest and companionship. Being who he was, both as a Spartan and as a man, John hadn't said anything, though Cortana had quietly approached several psychiatrists while they were onboard about the lack of interaction the Chief had with other soldiers, who often though he was a robot or unapproachable. To be honest, he never tried to dispel those rumors, at least not actively, but Cortana had been worried for him.

The last psychiatrist, however, had told Cortana that the man needed to want the interaction himself, and that her "meddling in his private affairs" would only distance them. Not wanting to risk that – it was a very real possibility that John would ask for a different AI if she started mothering him – she had simply remained silent on the issue.

Now, however, surrounded by a very obviously civilian family, unconventional as they were, and especially such an enthusiastic young man as Mikey, John was learning to relax a little. He still twitched at every sound that he wasn't expecting, and ate, spoke, and sat with the rigid military discipline to famous to Spartan soldiers, but the doors he had closed were starting to crack open. Best of all, the mutant turtles were treating him like a human being.


	2. Chapter 2

_Due to popular demand, I am continuing this story. Please let me know what you think! I started writing this before the 2012 toon, just so you all know. I apologize for the age discrepancy, I messed up, but will be rolling with the mistake!_

**Chapter 2: Getting to Know You**

John opened his eyes and, for a split second, couldn't remember where he was. Then he smelled the faint, earthy smell of brick, a headier scent of sweat, and a special smell he'd started to suspect was actually turtle-scent and remembered his misadventure. He rolled over onto his side; Cortana's holographic avatar appeared instantly on the small bedside table where he'd left her holotank.

"Good morning," she said softly when he shielded his hand against the sudden blossom of light.

"Good morning," John replied. "What time is it?"

"Well, technically, it's nearly six in the evening. Donatello said the turtles do not typically rise before eight or nine."

"So I've got a couple hours to myself."

"So it would seem. Where were you thinking of going?"

"Up top. I want to see what this city is like."

"Will you take me with you?"

"Of course." He smiled and stood, shivering as the cold sewer air hit his bare skin. He crossed to the small table that his clothing sat on, neatly folded; his hosts hadn't had an extra dresser, but the table worked well enough. He quickly pulled on a pair of black boxers, grey sweat pants, and a white T-shirt with a grey hoodie over it. The sweater's hood would keep him from attracting too much attention due to his scars and would keep the ports in the back of his neck invisible.

"I think I could get used to seeing you like that," Cortana chuckled softly. John shook his head slightly.

"It doesn't feel right," he told her, knocking the sweater's hood back with one hand. "Too baggy and… There's no pockets." He searched the pants but only found a pocket in the hood's front where he could tuck one or both hands – and quite a bit in the way of supplies.

"Well, just don't try to look menacing and this should be easy. Don't talk to anybody, though. Your accent will give you away."

"My accent?" John asked, trying to listen to himself speak.

"John, you've got a Reach accent – which isn't very different from an American one, sure, but more importantly, you speak like you're in the military, and that'll prompt questions that I don't think you want to answer. Now yank me and let's go for a walk."

John obligingly pulled her chip from the bottom of the holotank and slotted it into the port in the back of his head carefully. He felt her icy coolness meld with his brain; his vision spun for a single second and then settled, and he could feel her zipping through his neural network. They couldn't speak like this, but she could, at least, read the electrical signals in his brain to interpret the world around them – and even send a few of her own.

After a moment's thought, John put his pistol back on the table. He didn't expect to run into trouble this early in the evening, after all.

Then he walked silently out of his room, leaving the door open by habit, and to the kitchen. He had seen a notepad and pen in here earlier – he found both on the kitchen table and wrote a quick note in case someone woke to find him missing. He didn't want anyone thinking he was either lost or had been pulled back into his dimension – Donatello would like rip his armor apart instantly in an effort to understand it.

Then John stepped into the elevator. He could see a light shining dimly in the dojo, but Michelangelo had indicated that that area was off-limits so he ignored it. The doors closed silently and he rode up to the garage Don had shown him after dinner.

He ignored the bikes – Raph's crotch-rocket looked like it would fall apart given a few gentle kicks – and various other machines in states of repair – or disrepair – and walked out of the building. From the outside, it looked just like an abandoned warehouse. He paused for a moment to look back at it and then looked around.

This area of the city was squalid, but just a few blocks to the north lay several excellent shops, according to the two humans he had also met last night. Above, clouds and smog obscured what was left of the daylight, though John wouldn't be in danger of needing a flashlight for another two hours, he guessed.

The smog did diffuse the light so that the city looked like it was wreathed in a halo of yellow illumination, highlighted here and there with sparks of neon color. He looked straight up, watching his breath fog in the air; the moon was just another brighter shadow in the clouds.

_It's been a while since I've been dirt-side without a battle raging nearby_, John thought, consciously shaping the words so that Cortana could "read" them in his brain. He felt a stirring of agreement in the back of his head. _Can you see?_ Again, the same note of agreement, like a faint music playing just beyond his hearing range. He looked a little longer, knowing that Cortana would be savoring the pictures – and comparing them to databases – and then picked a destination at random from the buildings he could see.

His footsteps first crunched through gravel and then tapped softly on concrete as he walked quickly – not hurrying but with a destination in mind – towards the city. The road leading to the warehouse was a small one, clearly out of use, but it opened onto a busier street lined with two-meter-wide sidewalks. People thronged back and forth; John stood at the edge of the crowd to observe it for a moment.

Children as young two or three walked along with their parents or guardians, their hands firmly clasped in the adult's. Strollers with one or two babies or toddlers dotted the crowd, though not too many. Most of the people were dressed in what John assumed was business casual clothing – pants or longish skirts for the women, khakis for the men, button-down shirts for both. A few pairs of people – mostly heterosexual, John noted – were dressed up or down. A gaggle of teenagers trotted past and John could smell alcohol on them. An elderly couple meandered westward, the grey-haired wife holding onto her bald husband's arm.

John's height allowed him to look over the crowd and so he watched the cars for a moment, too. Yellow cabs with "TAXI" blazoned on their sides, their white and black stripes making them even more visible in the traffic, zoomed by, taking chances that the Spartan wouldn't in a Warthog.

_Maybe I should get driving lessons from them_, he thought humorously, watching as a taxi sped around a slower black car in the left lane. The squeal of brakes and an angry shout from further down the street attracted the Spartan's attention, but no one else turned to look. A middle-aged man thumped a taxi on the hood in anger as he crossed on the crosswalk.

Beyond the cars was the other sidewalk, similarly thronged with people, and shops interspersed with restaurants. A few doors down was the entrance to a clean but still seedy-looking hotel with a ratty red mat spread out in front of the doorway; that hotel soared ten stories up, at least two stories taller than any other building on this particular block. John could see skyscrapers in the distance that likely topped eighty floors at the lower end and a hundred at the upper.

The smell of cooking food was inviting and John waited for a break in the crowd to step into the sea. He let it move him along the block, cross the next street, and keep going. He passed through a well-to-do neighborhood with two hotels filling both sides of the street, loudly in competition. One was decorated for Halloween, with orange netting and ghosts hung about the front and in the windows. The other was more quietly preparing for the upcoming holidays; John could see a space inside clearly destined for a Christmas tree.

He caught snatches of conversation but didn't pay attention to any of it as he walked through the streets, purposefully keeping his mind actively thinking about the scenery so that Cortana could more easily access the information and "see" through his eyes.

Near the entrance to an alleyway, John stepped to the side to peer down the filthy, stinky sidestreet. Several dumpsters and garbages dotted the block as well as at least four homeless men that John could identify under rotting cardboard. One looked dead; the other three were moving.

_Sad_, Cortana "said" quietly in the back of his head.

John focused more closely on the apparently-dead man and saw two things. One, that it was a woman, judging by the protrusions on her chest, and two, that she was breathing. John could feel a low anger bubbling under his thoughts, both his and Cortana's.

_I don't have anything to give except the promise that worse is coming,_ John thought sourly, leaning against the filthy brick wall of the alleyway. A cat upset a pile of trash and meowed loudly in protest, stalking away from the offending mess with tail held high.

Cortana didn't reply except with a tiny wave of reassurance. John stood up and moved back into the throng of the crowd, paying less attention to his surroundings than to his thoughts.

_There must be these problems on our Earth_, he thought, glancing resolutely away from another alleyway as he passed it. Being helpless to help someone was an alien feeling to the Spartan; he didn't like it one bit. _And on the Outer Colonies before the Covenant glassed them. _He decided to discuss the issue with Cortana – thinking of her sparked a warm outpouring of support in the back of his mind – when she could respond more clearly.

The rest of the walk was quiet. John spotted more homeless people, some in better shape than others, often lying on or under rotting garbage and cardboard, their feet wrapped in newspapers. He passed men and women who smelled of cigarettes, alcohol, and other unidentifiable cocktails of addictive substances; more who smelled of perfume or cologne moved quickly past him.

Children just barely learning to walk sat on their parent's shoulders or in strollers, while elderly men and women stepped their slow way to and fro. He passed someone with a seeing-eye dog, who was given a conscious berth by the crowd, though several children giggled at the dog and wanted to pet her. A few teenagers wore huge headphones over their ears, listening to music he could hear, and John had to wonder if they were intentionally destroying their eardrums. A young woman accidentally bumped into him as she was backing up, trying to get a picture of a storefront; he smiled at her apology and kept moving.

The chaos of the street started to annoy him. These people weren't aware of the terrors that awaited their descendants, nor did they seem to be living in daily fear of a Covenant ship appearing overhead and raining fiery death down upon them. John stole into an alleyway to catch his breath.

John could feel Cortana's worry in the back of his mind and closed his eyes. Peace – that was what was unsettling him. The downright _peacefulness_ of the city was getting under his skin. There was murder, rape, homelessness, theft, and drug dealing here, he had seen evidence of all of that, but there was no unifying fear, no terror that overstepped the boundaries of human comprehension. He had grown up in a military area where fear was stamped out and then lived most of his "adult" life since fourteen in a universe terrorized every waking moment by the Covenant.

"Hey, buddy, got a light?" a young gentleman asked, leaning against the wall next to John. John shifted and shook his head, opening his eyes again. The man nodded unhappily and moved away, looking for someone else to bum off of.

John, for his part, watched the man for a moment before turning around and heading back towards the warehouse. The stench of the city made him yearn for the stale, clean smell of a ship's air or the gunpowder- and plasma-ridden scent of a battlefield. He'd even take the blood-and-warm-metal smell of a medical bay over the diseased city's air.

The night was turning truly dark when he arrived back at the warehouse. He stopped for a moment to look back at the city that surrounded the run-down hidden garage. No one would suspect that four mutant turtles and their mutant rat father lived here. It made him wonder what else hid in this city.

_~~TMNT~~_

Raph growled softly to himself, swinging a leg. '_Go find the Spartan, Raph,'_ he thought to himself, mimicking Leo's authoritative tone – in a totally girly voice. _Like I don't have enough to do on my own. 'Sides, not like he could possibly get into too much trouble on a _walk_. _

Raph looked up as he heard gravel crunching and saw John walking towards him. The Spartan was wearing sweats, his hands tucked into the pouch in front of him. Watching him walk, Raph had to admit that he just oozed power.

The man halted and turned back to look at the city, something unidentifiable yet sad in his face. Unwilling to risk trying to surprise the large man, not wanting a repeat of the incident on his ship, Raph coughed quietly.

"Good evening," John replied without twitching.

"Out fer a stroll?" Raph growled. The man's utter calm just pissed him off.

"Something of that nature, yes." John was still looking at the skyline. "I can count on one hand the number of times I have seen a city as peaceful as this."

"Peaceful?" Raph snorted, throwing a piece of gravel idly at the man's head. It bounced off his skull; John ignored the turtle. "This place ain't peaceful. We've got rape, abuse, theft, murder – things I ain't even got a name for."

Raph could make out a twist of John's lips in the darkening light when the man turned towards him. "But there is no danger that everything on this planet will be slag tomorrow," he replied softly. "There is threat, yes, but it is understandable – human. So… Peaceful. Or as close as I've ever seen."

"Ya lived a screwed up life."

John shook his head with a slight shrug. "Some would think so. I do not agree."

"Ya don't have a family, ya spent yer life fightin', and you think the Big Apple is peaceful. That's pretty screwed up in my book."

But John simply smiled. "I had a family, the best a man could ask for. My life has been spent protecting people, and again, what more could I want?"

"A life."

John climbed up to sit next to Raph, pulling his hood back to enjoy the rancid breeze. "If you had been raised a human, Raphael, would you think of your life as a turtle as not really a life?"

"Yeah, but I got my bros and Sensei and Casey. I've got hobbies – things I enjoy doing fer the heck of it. Like sneakin' out to piss Leo off."

"War doesn't leave time for fun when you're one of thirty-odd soldiers who can hold a candle to some of the things the Covenant can put out."

"Guess not." Raph sighed. "Still, Soldier Boy, yer a stick in the mud."

"Likely so," John replied. "But if we can't get home, I'm going to have to learn to integrate with your humans. Which is why I went out for a walk."

"Like whatcha see?" Raph asked, propping a foot on the roof and resting his chin on his knee. "Ain't much, but there's certain aspects…"

"I saw more than I wanted to." John shifted backwards and then swung his legs under him so that he was sitting cross-legged. "Homelessness, drug problems, relationship abuse – those are issues I never saw or dealt with. I'm sure the Outer Colonies had trouble with them, and I learned about some of that in the abstract, but I've never seen it. There were men and women lying in street trash and no one was looking at them, pretending they didn't exist." John could hear the frustration in his voice and paused, feeling a current of warmth from Cortana in the back of his head.

"It may seem petty to you," Raph allowed, speaking slowly as though working through his thoughts as he spoke them, "but we don't have a giant war uniting humanity. In fact, they're pretty damn un-united."

John nodded solemnly. "If your planet follows the course of mine… It will get worse before it gets better."

"I don't even wanna know."

John nodded in agreement. "I wouldn't tell you even if I knew your planet was going to go the same way. Your history has to unfold itself, and I won't push it either way."

"Yer a super-human soldier who may not be able to get home. You're going to affect things. We've hopped dimensions before, and trust me, you can _try_ not to interfere but you ain't gonna succeed."

"Then I will minimize my involvement."

Raph just snorted. They sat in companionable silence for a few minutes longer before Raph glanced down at the warehouse. "They're gonna wonder if we got in a fight," he said, smirking at the Spartan. "We should probably get down there so they know we didn't kill each other."

John raised an eyebrow. "You're assuming two things: that you _could_ kill me, and that I would kill you."

"Tough words for an old man," Raph snorted, hopping down from the warehouse roof. John didn't bother with a retort except to land next to the turtle heavily, emphasizing his size by straightening slowly.

They headed inside and down to the main lair, where Leo was just heading for the elevator. "There you are!" he said, exasperated. "I was beginning to worry…"

"That we'd killed each other," Raph finished, rolling his eyes and crossing his arms. "Nah, Leo. Quit being such a worrier."

"Actually, I was starting to worry that you'd gotten lost," Leo admitted, grinning slightly at the Spartan. "New York's a big place."

John shook his head. "I didn't go far enough that we couldn't find our way back."

"Do you have Cortana somewhere? Don was hoping to spend some time with her before we leave…"

John nodded, flipping the hood of his sweatshirt back and blanking his mind for a moment. Cortana indicated she was ready and he pulled the chip smoothly out of the port in the back of his neck.

"That's gross." Raph walked towards the kitchen, rubbing a hand over his masked eyes as though to wipe the image from his brain.

"She's on there?" Leo asked curiously, looking at the small chip in John's large hand.

John nodded. "It's her main matrix," he explained. But the perplexed look on Leo's face said he'd lost the turtle. "Kind of like her brain. She can "read" my brain's electrical signals – rudimentary; the armor improves our connection – and express some of her own." He tapped his head for emphasis.

"Telepathy?" Leo sounded unsure.

"Something like that," John agreed. "But much subtler. I can get hints of feelings from her, but she can read everything going on around me and inside my head."

"That sounds very…" Leo frowned, searching for a word. "Close. Having someone know your every thought?"

John tilted his head, confused. "It enhances my efficiency on the battlefield and improves real-time reports," he explained. Leo looked even more puzzled.

"Right, but what if you wanted to keep a secret?"

"We don't keep secrets from each other."

"I don't know if I could trust anyone like that. I like my privacy." Leo frowned slightly, clearly thinking deeply.

John nodded but didn't quite comprehend Leo's reluctance. Spartans didn't have privacy, after all, not from each other – and John couldn't imagine wanting to hide something from Cortana. He depended on her in battle, just as she did on him; secrets between them would erode that relationship and degrade their efficiency. The only secrets he kept were classified military information.

"Well, Don's in his lab if you want to drop her off. I, uh, don't know what you'd like to do while we're out, but we've got a TV, cable, books to read, and Don's probably got a laptop you can use if you want," Leo said.

John nodded thoughtfully, thanking Leo for the suggestions – he wasn't used to having free time, after all, especially without a gym – and heading towards Don's lab.

"Good evening," Don said cheerily. "How was your walk?"

"Interesting," John replied. "You're leaving soon on your patrol?" He noticed that Don was packing some things into a smallish duffle.

Don nodded. "Yeah, soon as it gets dark enough. We'll probably swing by the junkyard, but it's been pretty quiet lately, so we'll be back before too long. Feel free to use any of the computers in here if you like."

"Thank you." John slid Cortana's chip into her base here in the lab; she appeared on one of the computer's screen. "I assume you can entertain yourself," he told her, "without invading the government's files."

"I might take a peek," Cortane replied cheekily. "Might also made _you_ an identity – I've got your fingerprints on file. Worse comes to worst, Raph roughs you up a bit and you go find a hospital claiming amnesia."

"How long have you been planning that?" Don asked curiously, hiking the bag over his shoulder.

"Since we got here and learned about your world," Cortana admitted, smiling at the turtle.

"That actually just might work. _If_ you can explain the height, speed, strength, and scars," Don said.

"And a military career – I can fake black files for that. My original programming includes some of the best infiltration software of _my_ time. Your government won't see me coming."

"Let's hold off on that until we're sure we need it," John suggested. "And if I go to a hospital, they'll insist on a body scan, and there's no way to hide the augmentations to my skeletal structure – not to mention the implants in my brain." Don looked fascinated and John hoped the turtle didn't get any ideas.

"Touché," Cortana agreed. "Maybe not a hospital, then. You could always move to the middle of nowhere and live like a hermit."

"Which wouldn't help get us back to our time," John replied.

"I'll think of something," Cortana promised, already sounding thoughtful. "Go play a video game or something."

"Right." John frowned slightly.

"Alright, well, see you in a few hours," Don said, smiling at Cortana. "You can contact us if you need to; just ask Master Splinter for his shell cell. It's pretty easy to use."

"Have a good patrol," Cortana replied, chipper. John nodded in farewell as Don left the lab. John could hear Leo rousing Mike out of his room – much to the younger turtle's annoyance – and then the four turtles left.

The lair was silent with them gone; John looked back at Cortana to see her smiling slightly. "I like them," she acknowledged. "Would you bring in my holotank? I feel really flat without it."

John nodded and did as she asked, bringing her tank back from his room. He plugged it in and she transferred over with a contented sigh. "Thanks, John."

"You're welcome." John looked over at the pile of his armor, neatly stacked and cleaned and repaired. He could spend an hour checking it over again. As he was moving towards it, however, he heard the soft tap of Master Splinter's cane approaching and turned towards the door.

"Good evening," the rat said quietly, nodding to both him and Cortana.

"Good evening, sir," John replied.

"Good evening," Cortana echoed, turning around to smile at him. "How are you?"

"Doing well," Splinter replied, his whiskers twitching as he smiled gently. "And yourselves?"

"We're good," Cortana replied. "We went for a walk this evening, and saw many things that… interested us."

"Both of you?" Master Splinter asked, slightly confused.

"I can see through the Chief's eyes," Cortana explained, tapping her holographic cranium. "So he took me with him. We don't get separated."

"I… See." Clearly, though, the rat was confused. "I came to invite you to take tea with me, Mr. Chief."

John nodded politely. "Just "Chief," sir," he corrected. "It's a rank, not a name."

"Then what is your name?" The rat's tone was respectful but John had never had the question asked of him before and glanced uncertainly at Cortana. She nodded encouragingly.

"John," John replied after a short hesitation. Master Splinter hummed thoughtfully.

"Then if you will join me, young man, we will take tea." The rat smiled pleasantly. "And you are welcome to come with us, Ms. Cortana."

Cortana shook her head, grinning wickedly at John. "No, thank you, Master Splinter. I think I'll stay here. Have fun now, John." John eyed her for a split second and then followed the rat into the kitchen.

"So," Master Splinter said as he walked slowly to a tall cabinet and pulled down a box of scented leaves. He set a black kettle on the stove, already filled with water, and turned a knob. "You told me your name, but you do not wish it to be known. If I may ask, why?"

John took down two mugs from the cabinet when it was clear Master Splinter wouldn't be able to reach them easily. The rat smiled in thanks. "Few know my name," John replied quietly. "Fewer still use it. To my allies, I am the Chief. To my enemies, the Demon."

"A name defines who you are – your family, your past and your present."

John didn't agree; he shook his head. "My family is all dead," he said. "My past, present, and future is warfare, death, and destruction. I'd rather not have a name to put to that."

"Our world must be peaceful compared to yours," Master Splinter replied, sitting down at the table and laying his cane over his knees.

John nodded, standing at the other end of the table. "Raphael said the same."

"Such war and bloodshed – I cannot imagine what you have experienced, child. And I cannot help but wonder how it has changed you from who you could have been." John blinked, tilting his head slightly in confusion. The rat smiled gently. "I believe that every person has a destiny. You can change it, if you work hard enough, and it is easier to change for the worse. Others can change it for you, whether or not you will it. And I sense that yours has been changed – irreparably." John was silent, unsure of how to respond.

The kettle's whistling caught John's attention and Master Splinter showed him how to place the loose balls of tea into an infuser, which then sat in a cup as he poured hot water over them. Master Splinter offered him a white lump of sugar, which he declined, and held the mug in one hand as the rat cupped his own mug, inhaling the warm steam with a small smile on his muzzle.

They remained in silence, which suited John just fine, for a moment while the tea cooled. Rather than gulp it down, however, John copied Master Splinter and sipped gently. The tea leaves had given the hot water a faint flowery flavor; as he let the tea linger in his mouth, he picked up hints of lighter flavors, including birch wood, which reminded him of sub-artic missions, mint, and other things he had no name for.

But he realized that he was waiting for the smell of gunpowder, the coppery hint of blood infiltrating everything he ate, drank, and breathed for hours if not days at a time. The warm, earthy smell of the lair filled his nostrils instead of the stale air of a ship or the burning ozone smell of a glassed planet.

"A cup of tea is so simple a pleasure, yet it speaks of peace, comfort, and family," Master Splinter said quietly, watching the Spartan's face carefully. "Things you have not had in far too long."

John hadn't realized his eyes had closed until he opened them again, looking at the rat warily.

"You remind me of my sons," the rat continued, staring through the Spartan. "You have the leadership and determination of my eldest, Leonardo. The inner fire and protectiveness of Raphael. Donatello's brilliance and curiosity. Michelangelo's heart and perseverance. These are excellent strengths. But you are stubborn and angry as well. Hurt by years of warfare and death. You place a very small value on life – especially your own." John blinked carefully, taking another sip of the tea still in his hand. "You need balance. All warriors require balance in their lives. There is too much darkness in yours."

"There's no time for fun when you're struggling for survival," John replied, a little gruffer than he meant to. But the rat simply smiled.

"Your struggle for survival is not so different from ours. The players, the scale – that may be different. But living in fear, not knowing if this is the day you are killed – or discovered, which is the same for us – that is something we share." John was silent; the rat dipped his head. "Have you ever tried meditation?"

John shook his head. "We learned how, but I never got good at it. Linda…" He paused, remembering his fiery-haired sister. "She practiced Xen and tried to teach us, but I never caught on."

"Would you be willing to try again?"

John frowned slightly. "I should concentrate on getting Cortana and I back to our dimension."

The rat nodded in agreement. "But you need Donatello's assistance, and he is not here." John nodded reluctantly. "It will not hurt. All I ask is that you try. If you do not wish to continue, there is no shame in that."

"Alright," John grunted.

"Then come, child." Master Splinter set his mug on the edge of the sink, checked that the stove was off, and made his slow way towards the dojo.

John set his mug down and followed the rat. They stepped into the dojo and John looked around. None of the gear was new, and all bore signs of heavy use, but it was familiar and comforting. The room smelled of sweat, though not human.

"Sit with me." Master Splinter sank gracefully, despite his age, to the floor in the middle of a cleared space. The mats were stained with blood and sweat. John sat down facing the rat.

"Now, release your thoughts. Simply exist." John put his hands on his knees obediently, palms up, and closed his eyes. He sank into a thoughtless trance, a half-sleep.

Master Splinter watched the man as he breathed, deeply and slowly. The mutant could faintly hear the Spartan's thunderous heartbeat slowing and felt the man relaxing, though he maintained a corner of his mind in complete alertness. The blank look on the man's face, his usual expression, evolved into a softer, more peaceful expression, though still just as blank. The Spartan was utterly still; even the rat's sons twitched occasionally when meditating.

The Spartan maintained that balance for a few long moments before Master Splinter sensed a shift in his consciousness. The man's eyes snapped open; the rat could smell a faint trace of fear-sweat before the Chief brought himself back under steely control.

Master Splinter watched silently as the man tensed and then forcefully loosened up again. "Try again, child," he said quietly once the man was back under control.

The rat patiently waited; each time the Spartan dropped into a deep meditative trance, he would snap out within moments, nervous fear and sometimes anguish racing across his face in fleeting expressions the rat had to watch carefully for. Master Splinter extended a soothing aura, but that just served to make the Spartan more nervous, though he didn't show it – and may not have even acknowledged it to himself.

"Enough," Master Splinter said after an hour of practice. The Spartan stood gratefully. "My sons should return soon. You have my permission to use the dojo as you like, though I do ask that you not use the weapons within – they are precious to us and you would likely not find them suited to you anyway."

The man nodded silently. A shadow had been building behind his eyes during the meditation practice; the rat hummed thoughtfully to himself, dropping quickly and easily into meditation even as the Spartan left, his footsteps a little more hurried than necessary.


End file.
